The present invention relates to a device for fastening an optical observation instrument, particularly an operation microscope, to a supporting stand.
Operation microscopes have illustrative use in microsurgery. In order that the operator can have both his hands free at all times for his surgical work, such microscopes are fastened to a supporting stand, and the stand must be so devised that the operation microscope can be brought into a specific position and held there.
The most frequently used type of stand is a portable floor stand, establishing a vertical column. In one known embodiment, such a stand is equipped with a vertically adjustable horizontal arm which is swingable by 360.degree.. By means of counterweight balancing within the vertical column, the horizontal arm remains securely at any desired height. Foot-actuated bolts, with brake blocks in the base part of the stand, permit rapid and dependable locking, at a given floor position. The operation microscope itself is attached to the horizontal arm by an articulation member and couplings, so that it can be brought into any desired position. In such position, its optical axis can be swung through a large angular region by rotation about a mechanical axis in a vertical plane.
In addition to floor stands, stands with wall or ceiling attachment are also know. They can be used only in a fixed or stationary context but have the advantage that they take up little space. They are generally equipped with a swivel arm which makes it possible to bring the operation microscope into any desired position in space, within a certain range.
The known stands described above all have the disadvantage that, with the operation microscope in a given operating position in space, the optical axis of the microscope is adjustable only in one plane. Only very expensive and costly stands, for instance for neurosurgery and ENT, are free of this limitation. In the Fisch and Yasargil stands, the operation microscope can be displayed in three degrees of freedom of translation and three degrees of freedom of rotation, with counterweight balancing in each case. However, such stands are too expensive for normal practice.